Stack control device for oil burner systems



Oct. 13, 1931. w. w. WILLIAMS 1,827,703

STACK CONTROL DEVICE FOR OIL BURNER 'SYSTEMS ,Filed Dec. 21, 1925 s sheets-sheet' 1 BYO/0 Q: N ATTORNEYS.

Oct. 13, 1931. l w. WILLIAMS 1,827,703

l STAGK CONTROL DEVICE FOR OIL BURNER SYSTEMS y Filed Dec'. 2.1' 1925 3 Sheets-Sheet 2 BY^au ATTORNEYS. l

Oct. 13, 1931. w. w. WILLIAMS STACK CONTROL DEVICE FOR OIL BURNER SYSTEMS Filed Dec. 2l, 1925 3 Sheets-Sheet I5 NVENTOR. WW.W| LL| AMS BY )ML ATTORNEYS.

Patented oct. 13, 1931 UNITED STATES PATENT OFFICE WALTER W. WILLIAMS, OF BLOOMINGTON, ILLINOIS, ASSIGNOR TO WILLIAMS OIL-0- MATIC HEATING CORPORATION, OF BLOOMINGTON, ILLINOIS, A CORPORATION 0F ILLINOIS STACK CONTROL DEVICE FOR OIL BURNER SYSTEMS Application led December This invention relates to improvements in electric control devices particularly adapted for use in liquid fuel burning systems and more particularly to what is termed in the trade as a stack control device for oil burning systems. vention is illustrated and described in this application as a stack control, yet, it it to be understood that other embodiments may be constructed for other installations for the purpose of controlling an electric circuit actuated by a rise and fall in temperature without departing from the scope of this invention.

It is an object of this invention to provide a device adapted to be installed upon the stack or pipe leading from an oil burning furnace to the chimney or smoke stack which will control an electric circuit transmitting electric energy to operate'a motor actuated oil burner by the rise and fall of the temperature within said stack, It is also an object of this invention to provide a device of this character with a thermal element entering within the interior of the stack and effected by the temperature therein to expand 'and contract and upon expansion or contraction to positively throw an electric switch to close or open an electric circuit therethrough. It is a still further object of this invention to provide a device of this character which upon the initial expansion or contraction of the thermal element will immediately operate to throw the switch to one position or the other and will allow further contraction or expansion of the thermal element without effecting the position of the switch, but which will immediately upon a reversal of the movement of the thermal element instantly throw the switch to the opposite position.

While a preferred form of this invention is illustrated upon the accompanying sheets of drawing yet it is to be understood that minor detail changes may be made therein without departing from the scope of this invention.

Figure 1 is a view in side elevation of anembodimentl of lthis invention, with parts broken away and partly in section.

Figure 2 is aview in frdnt elevation of the While the embodiment of this in- 21, 1925. Serial N0. 76,581.

lustrating the position of the switch whenV thrown into open position.

Fi ure 4 is a view similar to Fi ure 2 showing t e position assumed when t e switch is thrown into closed position.

. Figures 5 andati are views similar to 3 and 4 of a modified form of this invention;

This device is adapted to be attached to the stack or 'pipe leading from an electrically operated oil burner furnace or heater connect- -ing the fire boX or fire pot of such heater t0 the conventional chimney or smoke stack which is indicated by the dot and dash lines of Figure 1. The casing l which contains the switch mechanism is provided with la removable cover 2 and is secured to the stack by providing an opening therein of suiiicient size to receive the sleeve 3 provided with a flange adapted to be secured to the exterior of the rear of the casing 1. The sleeve 3 is passed through the opening provided in the stack and is secured thereto by the adjustable sleeve 4 mounted thereon being brought into engagement with the interior of the stack and secured in such a position by a set screw. The sleeve 3 is provided with a central bore and the rear of the casing is provided with an opening of similar size in line therewith. A shouldered shaft 5 is rotatably mounted within the bore of the sleeve 3 and extends within the interior of the casing 1 at one end,

. with the enlarged portion having its shoulder in engagement with the interior of the sleeve 3, which enlarged ortion projects into the interior of the stac and is preferably provided at its inner end with an enlarged cylindrical head having a transverse slot 6 therethrough.- A spiral coil '7 of thermal material, preferably formed of a bi-metal.

which liub is provided with a toothed wheel 9, the teeth 10 of which are preferably Aof the knife-edged type and may extend entirely around the wheel or only about the lower portion thereof under certain conditions.

A mercury tube switch 11 of commercial form is carried in a clip 12 mounted upon a pivoted member 13 mounted to rotate upon a block 14 secured to the rear of the casing l and at such a distance therefrom that the upper contracted portion thereof 15, which is preferably formed to terminate in a knifeedge, will be engaged by the teeth 10 of the toothed wheel 9. Counterweights 16 and 17 are preferably secured on opposite sides of the member 13 below its pivot 18 to normally maintain the member in a vertical positionwith its upper knife-edge normally entering beteween two of the teeth 10 of the toothed wheel 9 and in thisposition support the mercury tube switch 11 in a horizontal or neutral position whereby the mercury within the tube is out of contact with the terminals of the switch.4 As additional means for normally causing the pivoted member to assume this vertical position 'shown and to return the pivoted member to this position, flat compression springs 19 and 20 are secured to opposite sides of the casing 1 with their free ends slidably engagineV the counterweights 16 and 17. as shown in Figure 2.

In the type of mercury tube switch shown, the two terminals thereof are spaced apart and introduced at one end of the tube so that when the tube is tilted in the direct-ion shown in Figure 3 the mercury will accumulate in the lower end away from the terminals and when tilted into the position shown in Figure 4 the mercury will accumulate in the other end to engage and close the circuit between the two terminals. The terminals are connected by flexible leads 21 and 22 to binding posts or other electrical connections through which the electric circuit to be controlled passes.

In the embodiment of this invention illustrated, the parts are so arranged as to normally assume the position shown in Figure 2 and upon an increase in temperature to a predetermined degree in the stack, the thermal element in expanding will rotate the toothed wheel to throw the pivoted arm into the position shown in Figure 4, whereby the circuit is closed through the mercury tube switch 11. This action will takev place immediately upon the expansion of the thermal element 7 causing the rotation of the shaft 5 and a knife-edged tooth of the wheel to be immediately brought into engagementwith the knife-edged termination of the pivoted member 13 which will overcome the counterweights upon such member and the tension of the spring 2O toturn it about its pivot. A further e ansion of the thermal element 7 causing a urther rotation of the shaft 5 will about its cause the teeth 9 to wipe ever the knife edge 15 of the pivoted member without imparting further movement thereto, but at the same time holding said member against its normal.` tendency to returnfto the vertical and a tooth of the wheel 9 will always be in engagement with the knife edge 15 against such tendency so that as soon as the thermal element 7 begins to contract from Whatever degree it may have beenraised, the toothed wheel will be caused to rotate in the opposite direction bringing the adjacent tooth thereof in contact with the opposite'sideof the knife edge 15 and tilt the pivoted member toward the vertical position, and as soon as the movement of contraction of the thermal element 7 begins the counterweights 16 and 17 and the spring 2 0 will initiate a return of the pivoted member 13 to the vertical thereby causing the mercury in the tube 11 to flow away from the contacts of the switch to break the circuit therethrough, and upon further contraction, a further movement in the same direction will be imparted to the toothed wheel 9 causing the pivoted member 13 to be rotated ivot until it assumes the position shown in igure 3, and further rotation of the toothed wheel in the same direction will cause the teeth thereof to wipe over the knife edge 15 of the pivoted member 13. After the thermal element has contracted to normal or with the parts in the position shown in Figure 3, a predetermined increase in temperature will cause an expansion of said member to rotate the shaft and toothed wheel in the opposite direction acting upon the pivoted member 13 in the manner first described which will close the circuit through the terminals of the electric switch 11. The engagement between the pointed end 15 of the pivoted member 13 and the teeth 10 of the wheel 9 is a positive one and is in elfect a pawl and ratchet movement. There is a positive interlocking or engagement between the toothed wheel and pivoted member which will impart upon rotation of the wheel an instantaneous positive tilting of the mercury tube switch to open or close the circuit therethrough.

In the modication shown in. Figures 5 and 6, the operation is the same as hereinbefore described, the difference being in the specific means for returning the 'pivoted member to the normal or vertical position. In this type the counterweight 30 upon the pivoted member 13 is smaller than that shown in the first four figures and in place of the springs 19 and 20, pivoted bell crank levers 31 and 32 are substituted. These levers are. pivoted at their apeXes on'either side of the.-

vertical central line of the pivoted memb 13 with one arm of each arranged-paran theretoterminating in curved noses 33 and 3 adapted to engage' the sides of the pivoted member 13 when in 'ts normal vertical posi-- pivot so that its counterweight 35 acts in the same manner as the spring 19 to return the I.

pivoted member 13 to the vertical position as soon as the toothed Wheel initiates 'a rotation in the opposite direction. While the other bell crank lever 3Q remains inactive vas it is supported in the horizontal position by the stop 30. lVhen the toothed Wheel 9 rotates in a 4direction to close the circuit, as shown in electric circuit closer mounted upon said member, a plurality of engaging members mounted on the operating element adapted to engage one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer and upon further rotation in the same direction, to move out of engagement but maintain the circuit closure in the same position.

2. In a thermostatic controlled electric switch, a. rotatable operating element. a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member,a plurality of engaging members mounted on the operating element adapted to engage one of such members with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer. and upon further rotation in the same direction to move such member out of engagement but maintain the circuit closer in the same position.

3. In a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a. pivoted member, an electric V circuit closer mounted upon said lmember, a plurality of engaging members mounted on the operating element adapted to engage one of such members with one end of the pivoted circuitcloser carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit throu h the circuit closer, and upon further rotatlon in the same direction to move such member out of engagement but maintain the circuit closer in the same position, by the engagement of theneXt adjacent engaging member.

4. In a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of engaging members mounted on the operating element adapted to engage one of such members with one' end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon further rotation in the same direction to move such member out of engagement but maint-ain the circuit closer in the same position, and means normally maintaining the end of the pivoted member in engagement With the op erating member.

5. In -a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of engaging members mounted on the operating element including a toothed Wheel adapted to engage one of the teeth thereof with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuitN closer, and upon further rotation il the same direction to move such tooth out of engagement and Wipe the following teeth thereover to maintain the pivoted member in the turned position.

6. In a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in 'opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of engaging members mounted on theA operating element adapted .to engage one of such members With one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon further rotation in the same'direction 'to move such member out of engagement but maintain the circuit closet` in the same position, and means normally maintaining the end of the pivoted member in engagement with the engaging members of the operating member.

7 In a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted,upon expansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of engaging members mounted on the operating element adapted to engage one of such members with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon further rotation in the same direction to move such member out of engagement but maintain the circuit closer in the same position, and means normally maintaining the end of the pivoted member in engagement with the, operating member, and additional means to exert a return movement of the pivoted member to a normal vertical position.

8. In a thermostatic controlled electric switch, a circular rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of engaging members including spaced apart teeth mounted on the operating element adapted to en-y gage between two adjacent teeth one end of the pivoted circuit closer carrying member` and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer and upon further rotation in the same direction to move the engaged tooth out of engagement but maintain the circuit closer in the same p0- sition by bringing into engagement the succeeding teeth and adapted upon rotation in the opposite direction to immediately engage between two adjacent teeth and return the circuit closer to the irst position.

9. I-n a thermostatic controlled electric switch, a circular rotatable operating element, a thermal element adapted upon eX- pansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of engaging members including spaced apart teeth mounted on the operating element adapted to engage one of such members with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon further' rotation in the same direction to move the engaged toothout of engagement but maintain the circuit closer in the same po-` sition by bringing into engagement the succeeding teeth and adapted upon rotation in the opposite direction tot immediately engage between two adjacent teeth and return the circuit closer to the first position.

10. In a thermostatic controlled electric switch, a circular rotatable operating element, Y

a thermal element adapted upon expansion 'i and contraction to rotate the operating elementsi'n opposite dii ections, a pivoted member, ai electric circuit closer mounted upon said member, aplurality of spaced apart teeth mounted on the operating element adapted to engage one of such teeth with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon Jfurther rotation in the same direction to move the engaged tooth out of' engagement but maintain the circuit closer in the same position by Abringing into engagement the succeeding-teeth, and adapted upon rotation` in the opposite direction to immediately e11- gage between two adjacent teeth and return the circuit closer to the first position.

\ 11. In a thermostatic controlled electric switch, a circular rotatable operating element, a thermal elementy adaptedupon expansion and contraction to rotate the operating element in opposite directions, a pivoted ment succeeding teeth, and means normally maintaining the end of the pivoted member in engagement with the operating member and adapted upon rotation in the opposite direction to immediately engage between adjacent teeth and return the circuit closer to the first position..

l2. In a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a-pivoted member, an

electric circuit closer mounted upon saidv member, a plurality of engaging @members mounted on the operating element including a toothed wheel adapted to engage one of the teeth thereof with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit'closer, and upon further vrotation in the same direction to move such tooth out of engagement and wipe the following teeth thereover to maintain the pivoted member in the turned position and adapted upon rotation in the opposite direction to imengage the end between adjacent mediatel (l return the circuit closer to the first teeth an position, c

13. In a thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in lopposite directions, a pivoted member, an

electric circuit closer mounted upon said member, a plurality of radial teeth mounted on the operating element adapted to engage one of such teeth with one end of the pivoted circuit closer carrying member and uponrotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon further rotation in the same direction to move such tooth out of engagement but maintain the circuit closer in the same position by wiping the succeeding teeththereover and means normally maintaining the end of the pivoted member in engagement with the engaging members of the operating member, and adapted upon rotation in the opposite direction to immediate engage between adjacent teeth- 'and return the circuit closer to the rst position.

14. In a'thermostatic controlled electric switch, a rotatable operating element, a thermal element adapted upon expansion and contraction to rotate the operating element in opposite directions, a pivoted member, an electric circuit closer mounted upon said member, a plurality of radial teeth mounted on f the operating element adapted to engage one of such teeth with one end of the pivoted circuit closer carrying member and upon rotation of the operating element to turn it about its pivot to open or close the circuit through the circuit closer, and upon further rotation in the saine direction to move such tooth out of engagement but maintain the circuit closer in the same position by wiping succeeding teeth over the end thereof, and means normally maintaining theend of the pivoted member in engagement with the operating member, and additional means to exert a return movement of the pivoted member to a normal vertical position and adapted upon rotation in the opposite direction to immediately engage 4the end between adjacent teeth and return the circuit closer to the first position.

15. In a thermostatic controlled electric switch, a rotatable toothed disc, a thermal element adapted upon expansion and contraction to rotate the disc in opposite directions,

a switch operating arm mounted therebelow, having a free end adapted to enter between adj acent disc teeth when in line with the centers of the disc and arm mounting, electric switch contacts, means coacting with the operating arm to open and close said contacts, the rotation of the disc .in one direction moving the free end of the arm to close said contacts, and rotation of the disc in the opposite direction engages the adjacent disc teeth to move the free end of the arm in the opposite direction to open said contacts.

16. In a thermostatic controlled electric switch, a rotatable toothed disc, a thermal element adapted upon expansion and contraction to rotaie the disc in opposite directions, a

switch operating arm mounted therebelow,

having a free end adapted to enter between adjacent disc teeth when .in line with the centers ot' the disc and arm mounting, electric switch contacts, means coacting with the operating arm to open and close said contacts, the rotation of the disc in one direction moving the free end of the arm to close said contacts, continued movement in the same direction passing the engaging disc teeth over the free end ot' the arm and engaging the succeeding' following teeth therewith to maintain the contacts closed, and rotation of the disc in the opposite direction engages the adjacent disc teeth to move the free end of the arm in the opposite direction to open said contacts. j

17. In a thermostatic controlled electric switch, a rotatable toothed disc, a thermal element adapted upon expansion and contraction to rotate the disc 1n opposite directions, a switch operating arm mounted therebelow, having a free end adapted to enter between adjacent disc teeth when in line with the centers of the disc and arm mounting, electric switch contacts, means coacting with the operating arm to open and close said contacts, the rotation of the disc in one direction moving the free end of the arm to close said contacts, rotation of the disc in the opposite direction engages the adjacent disc teeth to move' the free end ofthe arm in the opposite direction to open said contacts, and means exerting a return movement of the arm.

181y In a vthermostatic controlled electric switch, arotatable toothed disc, a thermal element adapted upon expansion and contraction to rotate the disc in opposite directions, a switch operating arm mounted therebelow, having a free end adapted to enter between adjacent disc teeth when in line with the centers of the disc and arm mounting, electric switch contacts, means coacting with the operating arm to open and close saidcontacts, the rotation of the disc in one direction moving the free end of the arm to close said contacts, continued movement in the A same; direction passing the engaging disc teeth over the :free end of the arm and engaging the succeeding following teeth therewith to maintain the contacts closed,n rotation' of the disc in the opposite direction engages the adjacent disc teeth to move the free end of the arm in the opposite direction to open said contacts, and means exerting s. return movement of the arm.

WALTER W. WILLIAMS. 

